on the Light emitted from various Bodies. 165 



appear : they likewise demonstrate, that as soon as a great 

 degree of putrescence has taken place, the luminous property 

 of the fishes is destroyed, and the light extinguished. 



Obs. 2. In the instance of light proceeding spontaneously 

 from animal flesh, recorded by Aquapendente, the flesh emitted 

 light before any sensible putrescence had taken place, the meat 

 being hung up in the larder for use. In that also mentioned 

 by Bartholin, in 1641, the flesh must have been fresh and 

 sweet, for it was not intended to be dressed until the next 

 day. Mr. Boyle, in his report of light issuing from flesh, ex- 

 pressly says, that neither he, nor any of those who were 

 about him, could perceive in it any offensive smell, whence to 

 infer any putrefaction ; the meat being judged very fresh, and 

 well conditioned, and fit to be dressed. And, lastly, Dr. 

 Beale, in his account of a luminous neck of veal, says, that 

 when it was dressed, on February the 27th, some of the 

 neighbours, who saw it shining, were invited to eat of it, and 

 all esteemed it as good as they had ever tasted ; that a part of 

 it was kept for February 28th and 29th, in which time it lost 

 nothing of its sweetness. 



Obs. 3. Whenever I wish to obtain a plentiful supply of light 

 from fishes, for the purpose of experiments, I always endeavour 

 to procure the freshest that can be had: long experience and 

 frequent disappointments have taught me to adopt such a pre- 

 caution. 



SECTION II. 



The Light here treated of is a constituent Principle of some 



Bodies, particularly of Marine Fishes, and may be separated 



from them, by a peculiar Process ; may be retained, and rendered 



